The study reports the results of a meta-analysis about the efficacy of
interactive programs to prevent drug abuse within the school setting in
Spain. 9 research reports from 1985 to 2002, were used to identify 15 independent
studies which complied with the selection criteria. The global effect size revealed that school programs to prevent drug abuse are efficient,
though its efficacy postest is small (d+= 0,20), tending to increase at
the follow-up (d+= 0,38). The programs turned out to be more efficient
with alcohol, than with tobacco or other drugs. Also the programs were
more successful in reducing drug use and improving knowledge than in
changing attitudes towards drugs. The component that apperared in all
the programs was providing information about substances. These findings
and some suggestions for future research are discussed.